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Updated technical information chapter (projections), extended glossary and abbreviations

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......@@ -4,6 +4,17 @@ All notable changes to this project will be documented in this file.
This project adheres to simple calendar versioning.
## 2024-12-29
## Added
- Extended glossary
- Extended abbreviations
## Changed
- Updated technical information chapter
## 2024-12-28
## Added
......
......@@ -20,6 +20,10 @@ A semi-fluid, ductile layer of the Earth's upper [mantle](#mantle) located below
A low area in the Earth’s surface, often filled with [sediments](#sediments), studied for its potential as a resource reservoir.
### Bessel Ellipsoid
The Bessel Ellipsoid, introduced in 1841 by Friedrich Bessel, is an early mathematical model of the Earth's shape based on arc measurements in Europe. It was widely used in European [geodesy](#geodesy) throughout the 19th and early 20th centuries. The Bessel Ellipsoid provided a more accurate regional fit for Europe compared to global models at the time.
### Bouguer anomaly
A [gravity anomaly](#gravity-anomaly) that has been [corrected](#bouguer-correction) for terrain and elevation, used to study subsurface mass distribution. The anomaly is named after Pierre Bouguer (1698–1758), a French mathematician, geophysicist, geodesist, and astronomer.
......@@ -49,6 +53,10 @@ The overall [density](#density) of a material, including both solid particles an
CAD refers to software used to create precision drawings and 3D models. In geophysics and geology, CAD tools help design equipment, geological models, and infrastructure layouts, aiding in the visualization and planning of field operations and simulations.
### central meridian
The central meridian is the longitudinal line at the center of a map [projection](#projection) zone, serving as the axis of least distortion. It is crucial in coordinate systems like the [Universal Transverse Mercator (UTM)](#utm-universal-transverse-mercator) and other cylindrical projections. The central meridian helps minimize distortion near the middle of the projection zone, with distortion increasing as you move away from it.
### CODATA
CODATA is the Committee on Data of the International Science Council (ISC) founded in 1966 (at that time known as the Committee on Data for Science and Technology). CODATA's mission is to connect data and people to advance science and improve our world by promoting international collaboration to advance Open Science and to improve the availability and usability of data for all areas of research.
......@@ -88,6 +96,10 @@ Covariance Matrix Adaptation Evolution Strategy (CMA-ES) is an advanced [optimiz
The CPU is the primary component of a computer that executes instructions from software, handling general-purpose tasks. While versatile, CPUs are less efficient for parallel processing compared to GPUs.
## CRS (Coordinate Reference System)
A Coordinate Reference System (CRS) defines how spatial data is mapped to the Earth's surface. It includes parameters like datum, [projection](#projection), and coordinate units, ensuring that geographic data aligns correctly across different datasets and software. CRS is essential in [GIS](#gis-geographic-information-system), [geophysics](#geophysics), and geodesy for accurate mapping and spatial analysis.
### crust
The outermost layer of the Earth, consisting of solid rock. It is divided into oceanic and continental crust and varies in thickness, playing a key role in geophysical studies of [gravity](#gravity) and [magnetics](#magnetism).
......@@ -98,6 +110,10 @@ The outermost layer of the Earth, consisting of solid rock. It is divided into o
The graphical representation of data to help users understand trends, patterns, and insights, often used in subsurface modelling.
### datum
A datum is a reference framework for measuring locations on the Earth's surface. It defines the origin and orientation of a coordinate system, often based on an ellipsoid that approximates the Earth's shape. Datums are crucial in [geodesy](#geodesy) and [GIS](#gis-geographic-information-system) for accurate mapping and positioning.
### DEM
DEM (Digital Elevation Model): a 3D representation of a terrain's surface created from terrain elevation data. It is commonly used in geographic information systems (GIS), remote sensing, and various engineering applications to model landscapes and analyze topography.
......@@ -118,7 +134,7 @@ The sudden release of energy caused by the shifting of [tectonic plates](#tecton
### ENU system
The ENU system is a local geodetic coordinate system used in [geophysics](#geophysics) and navigation, where coordinates are defined relative to a specific point on the Earth's surface. The three axes are:
The ENU system is a local [geodetic](#geodesy) coordinate system used in [geophysics](#geophysics) and navigation, where coordinates are defined relative to a specific point on the Earth's surface. The three axes are:
- East (E): Positive towards the east.
- North (N): Positive towards the north.
......@@ -126,6 +142,10 @@ The ENU system is a local geodetic coordinate system used in [geophysics](#geoph
This system is essential for mapping, GPS positioning, and representing vector data.
### EPSG (European Petroleum Survey Group)
EPSG is a standard for [coordinate reference systems](#crs-coordinate-reference-system) and spatial data projections, widely used in [geodesy](#geodesy), [GIS](#gis-geographic-information-system), and mapping. The EPSG database assigns unique codes to coordinate systems, [datums](#datum), and [projections](#projection), ensuring consistency in geospatial data processing and exchange.
### expected value
Expected value is the average or mean value that one would expect from a random variable over many trials. It represents the central tendency of a probability distribution. In [geophysics](#geophysics), the expected value is often used in probabilistic models or [uncertainty analysis](#uncertainty-analysis) to predict the most likely outcome of a parameter based on known data or distributions.
......@@ -174,6 +194,10 @@ Unit of acceleration, named in honour of the Italian physicist and astronomer Ga
[:octicons-arrow-right-24: **Source 1**](https://www.britannica.com/science/gal)
[:octicons-arrow-right-24: **Source 2**](https://en.wikipedia.org/wiki/Gal_(unit))
### Gauss-Krüger Coordinate System
The Gauss-Krüger system is a transverse cylindrical map projection used primarily in Europe and Asia for large-scale mapping and [geodetic](#geodesy) surveys. It is similar to the [UTM (Universal Transverse Mercator)](#utm-universal-transverse-mercator) system but differs in zone width and reference conventions.
### Gaussian Quadrature
Gaussian Quadrature is a numerical integration technique used to approximate the integral of a function, particularly in potential field modelling and geophysical data analysis. It achieves high accuracy by selecting optimal points (nodes) and weights, reducing computational effort compared to standard methods like the trapezoidal rule. This method is essential in solving complex integrals arising in gravity and magnetic modelling.
......@@ -182,6 +206,10 @@ Gaussian Quadrature is a numerical integration technique used to approximate the
Genetic Algorithm (GA) is a heuristic [optimization](#optimization) technique inspired by the process of natural selection. It uses operations like selection, crossover, and mutation to evolve solutions toward optimal results. In geophysical modelling, GAs can be applied to fit observed [gravity](#gravity) and [magnetic](#magnetism) data by evolving [potential field](#potential-field) models over successive generations to minimize error or improve accuracy.
### geodesy
Geodesy is the science of measuring and understanding the Earth's shape, orientation in space, and [gravitational field](#gravity-field). It provides the foundation for mapping, navigation, and [geophysical](#geophysics) studies by establishing accurate coordinate systems and reference frames. Geodesy is essential for GPS, surveying, and monitoring Earth's [dynamic](#geodynamics) processes, such as [plate tectonics](#plate-tectonics) and sea level changes.
### geodynamics
The study of the forces and processes that drive the movement and deformation of the Earth's [crust](#crust), [mantle](#mantle), and [core](#core). It encompasses [plate tectonics](#plate-tectonics), [mantle convection](#mantle-convection), [earthquakes](#earthquake), [volcanic activity](#volcanic-activity), and the flow of heat and materials within the Earth. Geodynamics helps explain the Earth's changing structure and the physical mechanisms behind [gravity](#gravity), [magnetism](#magnetism), and [tectonic movements](#tectonic-plate).
......@@ -210,6 +238,10 @@ A process of using observed data to derive a model of the subsurface, e.g. for g
The branch of earth sciences that uses physical methods, such as [gravity](#gravity), [magnetics](#magnetism), and seismic waves, to study the Earth's structure, composition, and processes. Geophysics is essential for exploring subsurface features and resources and understanding [geodynamic](#geodynamics) activities.
### georeferencing
Georeferencing is the process of aligning spatial data to a known coordinate system so it can be accurately mapped. This involves assigning real-world coordinates (latitude/longitude or [projected](#projection) coordinates) to images, maps, or datasets. In [geophysics](#geophysics), georeferencing is vital for overlaying survey data onto base maps and ensuring accurate positioning in [GIS](#gis-geographic-information-system) applications.
### GIS (Geographic Information System)
A Geographic Information System (GIS) is a framework for gathering, managing, and analyzing spatial and geographic data. It integrates data layers with maps to visualize, interpret, and analyze relationships, patterns, and trends. GIS is essential in [geophysics](#geophysics) for mapping geological features, analyzing [potential fields](#potential-field), and managing survey data.
......@@ -276,6 +308,10 @@ GUI (Graphical User Interface): a visual interface that allows users to interact
In [geophysics](#geophysics), a half-space refers to a theoretical, homogeneous, and infinite subsurface region extending below a boundary, often used in mathematical models to simplify the study of [gravitational](#gravity), [magnetic](#magnetism), or seismic responses. It is assumed to have uniform properties such as density or magnetization, and is useful for approximating real-world conditions in [subsurface modelling](#subsurface-modelling).
### Hayford Ellipsoid
The Hayford Ellipsoid, also known as the International Ellipsoid of 1924, is a mathematical model of the Earth's shape, representing it as an oblate spheroid. It was one of the first globally adopted reference ellipsoids for [geodesy](#geodesy) and mapping, providing a standard for international measurements. The Hayford Ellipsoid approximates the Earth's surface more accurately than earlier models, aiding in the development of coordinate systems and geophysical studies.
### HTML
HTML (Hypertext Markup Language): the standard markup language used to create and design web pages. It structures content on the web using elements like headings, paragraphs, links, and images.
......@@ -418,10 +454,22 @@ A field, such as [gravity](#gravity-field) or [magnetics](#magnetic-field), wher
A scientific theory that describes the large-scale movement of Earth's [lithosphere](#lithosphere), which is divided into [tectonic plates](#tectonic-plate).
### PROJ
[PROJ](https://proj.org) (also knows as PROJ.4) is an open-source software library used for cartographic projections and coordinate transformations. It enables the conversion of geographic coordinates between different [coordinate reference systems](#crs-coordinate-reference-system) by applying mathematical models of the Earth's shape, such as ellipsoids and geoids.
### projection
A projection transforms the Earth's curved surface into a flat, two-dimensional map. This process inevitably introduces distortions in area, shape, distance, or direction. Different projections are chosen based on the purpose of the map and the region being represented. In [geophysics](#geophysics) and [GIS](#gis-geographic-information-system), projections are crucial for spatial analysis and accurate visualization.
## Q
## R
### reference meridian
A reference meridian is the prime longitudinal line used as the starting point for measuring longitude. It serves as a global standard for geographic [coordinate systems](#crs-coordinate-reference-system). The most widely recognized reference meridian is the Greenwich Prime Meridian (0° longitude), adopted internationally in 1884.
### remanent magnetization
The [magnetization](#magnetization) retained by a rock after the removal of an external [magnetic field](#magnetic-field), revealing past geomagnetic conditions.
......@@ -523,7 +571,7 @@ Uncertainty analysis involves quantifying the degree of [uncertainty](#uncertain
### UTM (Universal Transverse Mercator)
The Universal Transverse Mercator (UTM) is a global coordinate system that divides the Earth into 60 longitudinal zones, each spanning 6 degrees. It uses a transverse Mercator projection to map curved surfaces onto a flat grid with minimal distortion. UTM coordinates are widely used in [geophysics](#geophysics), surveying, and GIS for precise location mapping and spatial analysis.
The Universal Transverse Mercator (UTM) is a global coordinate system that divides the Earth into 60 longitudinal zones, each spanning 6 degrees. It uses a transverse Mercator [projection](#projection) to map curved surfaces onto a flat grid with minimal distortion. UTM coordinates are widely used in [geophysics](#geophysics), surveying, and [GIS](#gis-geographic-information-system) for precise location mapping and spatial analysis.
## V
......@@ -549,6 +597,18 @@ In **IGMAS+**, a voxel cube is a volume consisting of many sub-volumes, or [voxe
## W
### WGS84 (World Geodetic System 1984)
WGS84 is the global standard coordinate system and datum used for GPS. It models the Earth as an ellipsoid and provides a common reference frame for geospatial data worldwide. WGS84 defines the shape of the Earth and serves as the basis for most modern mapping, navigation, and geophysical applications.
### WKT (Well-Known Text)
WKT (Well-Known Text) is a text-based format used to describe geospatial data and [coordinate reference systems](#crs-coordinate-reference-system). It provides a human-readable way to represent geometric shapes (like points, lines, and polygons) and coordinate systems used in [GIS](#gis-geographic-information-system).
## WorldWind
[WorldWind](https://worldwind.arc.nasa.gov/) is an open-source virtual globe developed by NASA for geospatial data visualization. It allows users to interact with 3D representations of Earth and other celestial bodies, providing tools to overlay and analyze geospatial data, such as satellite imagery, terrain, and vector data. WorldWind is widely used in scientific research and [GIS](#gis-geographic-information-system). In **IGMAS+** [WorldWind Java](https://github.com/NASAWorldWind/WorldWindJava) is is used for visualizing gravity and magnetic data on the globe.
## X
## Y
......
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......@@ -287,7 +287,7 @@ You can check the units using **Preferences** (++"Edit"++ --> ++"Preferences"++)
For the modelling it is not necessary to use a special geographical projection, the only prerequisite is an **orthogonal coordinate system** - which may be any projection.
However, if you plan to visualize the model and the anomaly fields using WorldWind, you have to specify the correct projection.
However, if you plan to visualize the model and the anomaly fields using [WorldWind](./glossary.md#worldwind), you have to specify the correct projection.
Use the **Property editor** tab of the **Object Tree** entry **Model** to get the projection definition:
......@@ -295,9 +295,9 @@ Use the **Property editor** tab of the **Object Tree** entry **Model** to get th
#### Projection: unknown
Use this setting, if you don't know the projection being used, if you use local coordinates (not referred to world coordinates) or if you are not interested in visualization with WorldWind.
Use this default setting, if you don't know the projection being used, if you use local coordinates (not referred to world coordinates) or if you are not interested in visualization with [WorldWind](./glossary.md#worldwind).
#### Projection: Mercator
<!-- #### Projection: Mercator
The Mercator projection is the easiest way to transfer spherical (geographical) coordinates into plane (orthogonal) coordinates.
Use the following transfer functions - they are exact and easy to use:
......@@ -322,67 +322,129 @@ $\varphi = \arcsin (\tanh(y))$
The Mercator projection (used for rendering maps in Google Maps, OpenStreetMap, Bing etc.) is most accurate in the area of low latitudes, it cannot be used in polar regions.
:::
The EPSG code (see ) of this projection is 3857.
The EPSG code (see ) of this projection is 3857. -->
#### Projection: Universal Transverse Mercator
The [Universal Transverse Mercator (UTM)](./glossary.md#utm-universal-transverse-mercator) projection uses the Hayford ellipsoid.
The [Universal Transverse Mercator (UTM)](./glossary.md#utm-universal-transverse-mercator) projection uses the [Hayford Ellipsoid](./glossary.md#hayford-ellipsoid)/
The parameters are:
The parameters are: **Ref. meridian**, **UTM Zone**, **Hemisphere**, **East - Delta** and **North - Delta**:
Reference meridian
![Projections settings: Universal Transverse Mercator (UTM)](./media/projection_settings_UTM.png)
: May be -177, -171, -165, \... +177 (degree).
**Ref. meridian:**
UTM Zone
The central meridian (in **IGMAS+** called reference meridian) varies between -177° and +177° according to the table:
: May be 1 to 60. The zone is linked to the reference meridian via the
following equation:\
$zone = (Ref.Mer. + 183)/6$
| **UTM Zone** | **Central Meridian** | **UTM Zone** | **Central Meridian** |
|--------------|----------------------|--------------|----------------------|
| 1 | -177° W | 31 | 3° E |
| 2 | -171° W | 32 | 9° E |
| 3 | -165° W | 33 | 15° E |
| 4 | -159° W | 34 | 21° E |
| 5 | -153° W | 35 | 27° E |
| 6 | -147° W | 36 | 33° E |
| 7 | -141° W | 37 | 39° E |
| 8 | -135° W | 38 | 45° E |
| 9 | -129° W | 39 | 51° E |
| 10 | -123° W | 40 | 57° E |
| 11 | -117° W | 41 | 63° E |
| 12 | -111° W | 42 | 69° E |
| 13 | -105° W | 43 | 75° E |
| 14 | -99° W | 44 | 81° E |
| 15 | -93° W | 45 | 87° E |
| 16 | -87° W | 46 | 93° E |
| 17 | -81° W | 47 | 99° E |
| 18 | -75° W | 48 | 105° E |
| 19 | -69° W | 49 | 111° E |
| 20 | -63° W | 50 | 117° E |
| 21 | -57° W | 51 | 123° E |
| 22 | -51° W | 52 | 129° E |
| 23 | -45° W | 53 | 135° E |
| 24 | -39° W | 54 | 141° E |
| 25 | -33° W | 55 | 147° E |
| 26 | -27° W | 56 | 153° E |
| 27 | -21° W | 57 | 159° E |
| 28 | -15° W | 58 | 165° E |
| 29 | -9° W | 59 | 171° E |
| 30 | -3° W | 60 | 177° E |
Hemisphere
**UTM Zone:**
: North or South (Default: North)
The UTM Zone varies between 1 and 60 and is linked to the central meridian via the following equation:
East Delta
$$\mathrm{Zone} = (\mathrm{Central~Meridian} + 183)/6$$
: This value (in meters, default is 0) will be added to the model
x-coordinates before transformation into geographical coordinates.
UTM Zones 1 to 30 cover the western hemisphere (west of Greenwich).
UTM Zones 31 to 60 cover the eastern hemisphere (east of Greenwich).
North Delta
Each UTM zone spans 6 degrees of longitude, with the central meridian located in the middle of the zone.
: This value (in meters, default is 0) will be added to the model
y-coordinates before transformation into geographical coordinates.
**Hemisphere:**
Either North or South (Default: North)
North and South UTM Zones refer to the division of UTM zones based on the hemisphere:
- UTM North (N) Zones:
- Cover the northern hemisphere (from the equator to 84°N).
- Zone numbers range from 1N to 60N.
- Latitude values are positive, starting at 0 m at the equator and increasing northward.
- UTM South (S) Zones:
- Cover the southern hemisphere (from the equator to 80°S).
- Zone numbers range from 1S to 60S.
- Latitude values are negative, starting at 0 m at the equator and increasing southward.
- To avoid negative coordinates, false northing of 10,000,000 meters is applied at the equator.
**East Delta:**
This value (in meters, default is 0) will be added to the model $x$-coordinates before transformation into geographical coordinates.
**East Delta:**
This value (in meters, default is 0) will be added to the model $y$-coordinates before transformation into geographical coordinates.
#### Projection: Gauß-Krüger
The Gauß-Krüger projection uses the Bessel ellipsoid.
The [Gauß-Krüger](./glossary.md#gauss-kruger-coordinate-system) projection uses the [Bessel Ellipsoid](./glossary.md#bessel-ellipsoid).
The system is similar to the [UTM (Universal Transverse Mercator)](#projection-universal-transverse-mercator) system but the central meridians of the Gauss–Krüger zones are only 3° apart, as opposed to 6° in UTM.
The parameters are: **Ref. meridian**, **Hemisphere**, **East - Delta** and **North - Delta**:
![Projections settings: Gauß-Krüger (GK)](./media/projection_settings_GK.png)
The parameters are:
Zones of the Gauß-Krüger projections are defined by the central meridian (parameter **Ref. meridian**).
Each GK zone spans 3 degrees of longitude, with the central meridian located in the middle of the zone.
Reference meridian
**Ref. meridian:**
: May be -180, -177, -174, \... +180 (degree).
The central meridian (in **IGMAS+** reference meridian) varies between -177° and +177°.
Hemisphere
**Hemisphere:**
: North or South (Default: North)
Either North or South (Default: North)
East Delta
**East Delta:**
: This value (in meters, default is 0) will be added to the model
x-coordinates before transformation into geographical coordinates.
This value (in meters, default is 0) will be added to the model $x$-coordinates before transformation into geographical coordinates.
North Delta
**East Delta:**
: This value (in meters, default is 0) will be added to the model
y-coordinates before transformation into geographical coordinates.
This value (in meters, default is 0) will be added to the model $y$-coordinates before transformation into geographical coordinates.
#### Projection: European Petroleum Survey Group (EPSG)
The European Petroleum Survey Group (EPSG) established a system to define and access all geodetic coordinate projections used worldwide.
The [European Petroleum Survey Group (EPSG)](./glossary.md#epsg-european-petroleum-survey-group) established a system to define and access all geodetic coordinate projections used worldwide.
The website <http://epsg.io> may be used to find the EPSG code for a special projection.
The parameters are: **EPSG - Code** and **Proj4 Definition**:
![Projections settings: European Petroleum Survey Group (EPSG)](./media/projection_settings_EPSG.png)
By specifying the appropriate EPSG code code in the field **EPSG - Code** you can set up any projection.
Examples:
| **EPSG code** | **Description** |
......@@ -393,25 +455,69 @@ Examples:
| 31468 | DHDN, Gauß-Krüger Zone 4. Germany |
| 24819 | PSAD56, UTM Zone 19, Chile |
!!! note
If the EPSG code is used, the model coordinates have to be in **meters**, and there is no additional offset for the locations possible.
::: center
:::
##### PROJ.4 Definition
Each projection may be defined by a number of parameters and thus described by a single line definition - called PROJ.4 (<https://proj.org/>, see also <https://live.osgeo.org/en/overview/proj4_overview.html>).
[PROJ](./glossary.md#proj) (formerly PROJ.4) is an open-source software library used for cartographic projections and coordinate transformations.
The ideas is that each projection may be defined by a number of parameters and thus described by a single line definition using [PROJ](https://proj.org) syntax.
Example: The description of the EPSG code 24819 (UTM zone 19) is:
The PROJ definition is given for each projection on the [EPSG website](https://epsg.io), in addition it is always shown in the **IGMAS+** EPSG projection settings (see the previous figure).
You may alter the value under **Proj4 Definition** to define your own projection. (the **EPSG - Code** value is then set to 0).
???+ example
The Proj4 definition of the [EPSG code 24819](https://epsg.io/24819) (UTM zone 19N) is:
```plaintext
+proj=utm +zone=19 +ellps=intl +towgs84=-288,175,-376,0,0,0,0 +units=m +no_defs
```
+proj=utm +zone=19 +ellps=intl +towgs84=-288,175,-376,0,0,0,0 +units=m
+no_defs
```
See also [this archive article](https://live.osgeo.org/archive/11.0/en/overview/proj4_overview.html) for more information.
The PROJ.4 definition is given for each projection on the EPSG website, in addition it is always shown in the projection settings (see figure above). You may alter this line (EPSG code is set to 0 in this case) to define your own projection.
##### Mercator projection
#### Projection: GeoTools
The Mercator projection is the easiest way to transfer spherical (geographical) coordinates into plane (orthogonal) coordinates.
Use the following transfer functions - they are exact and easy to use:
Forward (spherical into orthogonal):
$$x = (\lambda - \lambda_0)$$
$$y = 0.5 \cdot \ln \left(\dfrac{1+\sin(\varphi)} {1-\sin(\varphi)}\right)$$
Here $\lambda$ and $\varphi$ are given in radians. $x$ and $y$ are normalized with the Earth radius, so multiply x and y with 6378137 to get meters or 6378.137 to get kilometers.
Reverse (orthogonal into spherical):
$$\lambda = \lambda_0 + x$$
$$\varphi = \arcsin (\tanh(y))$$
!!! note
The Mercator projection (used for rendering maps in Google Maps, OpenStreetMap, Bing etc.) is most accurate in the area of low latitudes, it cannot be used in polar regions.
The EPSG code of this projection is 3857.
#### Projection: GeoTools Projection
GeoTools is another open-source Java library designed for geospatial data processing. It supports projections and coordinate transformations by leveraging standards like OGC and EPSG codes. GeoTools is widely used in [GIS](./glossary.md#gis-geographic-information-system) applications to handle vector and raster data, offering robust tools for reprojecting spatial data between [coordinate reference systems (CRS)](./glossary.md#crs-coordinate-reference-system).
There is only one parameter, **EPSG - Code**:
![Projections settings: GeoTools](./media/projection_settings_GeoTools.png)
However, it is possible to provide information about the custom projection using the [WKT format](./glossary.md#wkt-well-known-text) by loading files with `*.wrt` and `.prj` extensions (++"Import WKT"++ button).
???+ example
A typical WKT string for WGS84 ([EPSG:4326](https://epsg.io/4326)) looks like this:
```plaintext
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563]],
PRIMEM["Greenwich",0],
UNIT["degree",0.0174532925199433]]
```
---
......
......@@ -3,10 +3,12 @@
*[CODATA]: Committee on Data of the International Science Council
*[CMA-ES]: Covariance Matrix Adaptation Evolution Strategy
*[CBA]: Complete Bouguer Anomaly
*[CSV]: Comma Separated Values
*[CPU]: Central Processing Unit
*[CSV]: Comma Separated Values
*[CRS]: Coordinate Reference System
*[DEM]: Digital Elevation Model
*[EGU]: European Geosciences Union
*[EPSG]: European Petroleum Survey Group
*[ES]: Evolution Strategy
*[ENU]: East-North-Up
*[FA]: Free-air Anomaly
......@@ -19,6 +21,9 @@
*[JRE]: Java Runtime Environment
*[JVM]: Java Virtual Machine
*[KTB]: Kontinentales Tiefbohrprogramm der Bundesrepublik
*[NASA]: National Aeronautics and Space Administration
*[OGC]: Open Geospatial Consortium
*[OpenCL]: Open Computing Language
*[OpenGL]: Open Graphics Library
*[UTM]: Universal Transverse Mercator
*[WGS84]: World Geodetic System 1984
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